1. Field of the Invention
The present invention relates to a quick connector to be coupled to a pipe having an annular boss.
2. Description of the Related Art
Connectors described in Japanese Unexamined Patent Publication No. 2004-003588 (Patent Literature 1), Japanese Unexamined Patent Publication No. 2011-174508 (Patent Literature 2), Japanese Patent Application National Publication (Laid-Open) No. 2008-512607 (Patent Literature 3), and Japanese Unexamined Patent Publication No. 2006-183833 (Patent Literature 4) each have a connector body and a retainer, the retainer being pushed into the connector body by the operator, thereby being locked to an annular boss of a pipe for retaining the pipe. To enable the pushing-in operation of the retainer, the insertion of the pipe into a normal position of the connector body is necessary. That is, in the connector, with the pushing-in operation of the retainer, it is possible to confirm the insertion of the pipe into the normal position.
In each connector described in Patent Literatures 1 and 2, in a state where the retainer is located at an initial position (the position of the retainer which has not been pushed into the connector body), when the pipe is located at the normal position, legs of the retainer are spreadingly deformed by the annular boss of the pipe. The spreading deformation of the legs of the retainer enables the pushing-in operation of the retainer. In each connector described in Patent Literatures 3 and 4, in a state where the retainer is located at the initial position, when the pipe is located at the normal position, legs of the retainer are pushed in the axial direction by the annular boss of the pipe, and are flexurally deformed in the axial direction. The flexural deformation of the legs of the retainer enables the pushing-in operation of the retainer.
However, in the connector, before the retainer is pushed into the connector body after the insertion of the pipe into the normal position, the legs of the retainer are brought into a state of being spreadingly deformed or into a state of being flexurally deformed in the axial direction. When the above states are continued for a long time, the legs of the retainer can be changed with time. In such a case, there is a fear that the retainer is movable from the initial position in the pushing-in direction even when the pipe is not located at the normal position.
The problems can be typically avoided by the quick operation of the operator. However, to enhance the safety, in a state where the retainer is located at the initial position, when the pipe is inserted into the normal position, the deformation amount of the legs of the retainer is desirably small.
In a state where the retainer is located at the initial position and in a state where the pipe is not inserted into the connector body, it is necessary to restrict the movement of the retainer from the initial position in the pushing-in direction by locking the retainer to the connector body. For this, the deformation amount of the legs of the retainer is increased when the pipe is inserted into the normal position, so that the movement of the retainer from the initial position can be reliably restricted in a state where the pipe is not inserted.
That is, to prevent the legs of the retainer from being changed with time in a state where the pipe is inserted into the normal position, it is necessary to decrease the deformation amount of the legs of the retainer in the state. On the other hand, to reliably restrict the movement of the retainer in the pushing-in direction in a state where the pipe is not inserted into the normal position, it is necessary to increase the deformation amount of the legs of the retainer necessary for releasing the restriction of the retainer to the connector body.
An object of the present invention is to provide a quick connector which can prevent legs of a retainer from being changed with time in a state where a pipe is inserted into a normal position and can reliably restrict the movement of the retainer in the pushing-in direction in a state where the pipe is not inserted into the normal position.